Aluminum clutch components with ferrous surface

Abstract

Components for an automatic motor vehicle transmission including a band brake drum, a clutch housing or hub having a seal surface or a clutch housing or hub utilized in a friction clutch assembly having a spline set. All of these components are fabricated of aluminum and the outer surface of the band brake drum, the housing or hub sealing surface and the area of the spline set includes a thin coating of a thermally sprayed steel material. The thermally sprayed steel material may be a low carbon steel such as SAE 1008 or 1010, a similar alloy, iron or other metal. The resulting components thus exhibit the weight saving of aluminum while providing excellent service life due to the enhanced strength and wear resistance provided by the thermally sprayed steel coating.

What is claimed is: 
     
       1. A unitary housing and hub assembly for an automatic motor vehicle transmission comprising, in combination,
 a first substantially cylindrical outer aluminum housing portion and a second substantially cylindrical inner aluminum hub portion coupled to the outer portion, the outer housing portion and the inner hub portion having inside surfaces defining a friction clutch receiving region, the inner hub portion also having an outside surface including a plurality of female spines and an inside bushing surface, the splines and the bushing surface including a non-aluminum metal coating. 
 
     
     
       2. The unitary housing and hub assembly of  claim 1  further including a friction clutch disposed in the friction clutch receiving region, the friction clutch having elements coupled to the inside surface of the outer housing portion. 
     
     
       3. The unitary housing and hub assembly of  claim 2  wherein the friction clutch includes at least one hydraulic fluid chamber and the housing and hub assembly includes at least one fluid passageway communicating with the hydraulic fluid chamber. 
     
     
       4. The unitary housing and hub assembly of  claim 3  further including at least a pair of seals disposed on opposite sides of the at least one fluid passageway. 
     
     
       5. The unitary housing and hub assembly of  claim 1  wherein the non-aluminum metal coating is one of SAE 1008 steel, SAE 1010 steel, iron, alloys and other metals. 
     
     
       6. The unitary housing and hub assembly of  claim 1  further including a plurality of radially extending fluid passageways in the inner hub portion. 
     
     
       7. A unitary housing and hub assembly for an automatic motor vehicle transmission comprising, in combination,
 a first substantially cylindrical outer aluminum housing portion and a second substantially cylindrical inner aluminum hub portion integrally formed with the outer portion, the outer housing portion and the inner hub portion having inside surfaces defining a friction clutch actuator receiving region, the inner hub portion also having a first surface including a plurality of female spines and a second bushing surface, the female splines and the bushing surface including a non-aluminum metal coating. 
 
     
     
       8. The unitary housing and hub assembly of  claim 7  further including a friction clutch disposed in the friction clutch receiving region, the friction clutch having elements coupled to the inside surface of the outer housing portion. 
     
     
       9. The unitary housing and hub assembly of  claim 7  further including at least one radially extending fluid passageway in the inner hub portion. 
     
     
       10. The unitary housing and hub assembly of  claim 9  further including a pair of seals disposed on opposite sides of the at least one fluid passageway. 
     
     
       11. The unitary housing and hub assembly of  claim 7  wherein the non-aluminum metal coating is one of SAE 1008 steel, SAE 1010 steel, iron, alloys and other metals. 
     
     
       12. A unitary housing and hub assembly for an automatic motor vehicle transmission comprising, in combination,
 a first substantially cylindrical outer aluminum housing portion and a second substantially cylindrical inner aluminum hub portion connected by a radially extending wall portion, the outer housing portion, the inner hub portion and the wall portion having inside surfaces defining a friction clutch receiving region, the inner hub portion also having an inwardly directed surface including a plurality of female spines and an outwardly directed bushing surface, and a non-aluminum metal coating disposed on the splines and the bushing surface. 
 
     
     
       13. The unitary housing and hub assembly of  claim 12  further including a friction clutch disposed in the friction clutch receiving region, the friction clutch having elements coupled to the inside surface of the outer housing portion. 
     
     
       14. The unitary housing and hub assembly of  claim 13  wherein the friction clutch includes at least one hydraulic fluid chamber and the housing and hub assembly includes at least one fluid passageway communicating with the hydraulic fluid chamber. 
     
     
       15. The unitary housing and hub assembly of  claim 14  further including a pair of seals disposed on opposite sides of the at least one fluid passageway. 
     
     
       16. The unitary housing and hub assembly of  claim 12  wherein the non-aluminum metal coating is one of SAE 1008 steel, SAE 1010 steel, iron, alloys and other metals. 
     
     
       17. The unitary housing and hub assembly of  claim 12  further including female splines on an end adjacent region of the outer housing portion.